European Patent document EP 0580 107 shows a magnetic suspension system which is designed for transport purposes using straight and curved path sections. The crucial point, in this instance, is the control of the air gap, as a function of the load of the secondary part, using a regulating device fixed to the secondary part. This regulation device is supplied with energy in a contactless manner, via an induction loop having a 10 kHz voltage source. The induction loop is, however, only present at the straight route sections. For travel on curves, a back-up battery situated on the suspension vehicle has to provide energy. Disadvantages of the system are that, on the one hand, the inductive energy coupling is not without gaps along the route, and, on the other hand, for the generation of an alternating field of high frequency, generally an additional expenditure for material, manufacturing and costs for the implementation is required, which increases in proportion to the route length, and therewith makes the components more expensive in an extreme manner (see, e.g., FIG. 6; column 11, lines 14 ff), as well as requiring regular maintenance.
U.S. Pat. No. 6,502,517 also shows a magnetic suspension system. Contactless energy transmission is also made the subject of discussion in this instance. However, a specific point of departure as to how this energy transmission could be implemented is hardly to be found here (see, e.g., FIG. 1, column 5, lines 19 ff and claims). It may also be clearly inferred from this document that the magnetic field for locomotion (reference points 8, 8.1 and 8.2, FIG. 1) and the device for energy transmission (reference point 9, FIG. 1) are constructed mechanically separated from each other. Consequently, similar disadvantages derive from this U.S. patent document as in the case of the arrangement described in European patent document EP 0580 107.
It is an object of the present invention to provide a contactless energy supply for electrical consumers applied to the moving part (secondary part) of a linear motor, without considerable additional material and/or manufacturing expenditure, and without additional voltage sources on the secondary part. Besides all this, the equipment should be largely not susceptible to faults.